15 votes

Why does photosynthesis specifically produce glucose?

Glucose is such a ubiquitous energy storage molecule, that we show the simple photosynthetic chemical equation to include the capture of six CO2 molecules to create one glucose molecule. However, the ...
Darlingtonia's user avatar
  • 2,582
7 votes
Accepted

Why is sugar absorbed very fast into the blood stream?

In short, sugars are absorbed quicker than proteins and fats because they pass through the stomach quicker and their digestion is simpler. Sugar can be absorbed through the mouth mucosa when applied ...
Jan's user avatar
  • 8,079
6 votes

Reason for conversion of glucose to fructose in glycolysis

Avoiding diffusion is one reason to phosphorylate glucose, the other is that it is removed from the osmotic balance between inside and outside of the membrane, so it can be transported at a high rate. ...
Chris's user avatar
  • 51.6k
5 votes

Why is GTP, not ATP, produced in Gluconeogenesis & TCA Cycle?

Nice question. Beginning with Krebs cycle, there is actually no specific answer as both GTP and ATP are produced. First, see this article for why GTP is the more frequent product: It may be that at ...
another 'Homo sapien''s user avatar
4 votes

How do absorbance readings indicate diauxic growth of bacteria?

How is growth rate an indicator of carbohydrate use? Carbohydrates are the carbon and energy source available for the microbes, and their assimilation is correlated to biomass production. The ...
Flo's user avatar
  • 707
4 votes

Why are only 6 water molecules formed in the aerobic degradation of glucose?

Your confusion comes entirely from this equation: $\ce{C6H12O6 + 6O2 -> 6CO2 + 6H2O}$ This reaction is the combustion of glucose. This is not how glucose is oxidized in cells! Why so many biology ...
canadianer's user avatar
  • 17.7k
3 votes
Accepted

Source of blood glucose during starvation

The (very) short answer is gluconeogenesis. When glucagon levels are high in response low glucose or low Insulin (perceived in the case of Insulin resistant DM Type II) key enzymes will be inhibited ...
kingfishersfire's user avatar
3 votes

What's the highest glucose concentration (in mM) anywhere in the human body (tissue, capillaries, tumor microenvironment, etc.)?

Glucose concentration in the blood is a highly regulated biologic variable. From personal laboratory experience, it is very difficult to raise a healthy, non-diabetic individual's blood glucose over ...
Vance L Albaugh's user avatar
3 votes

Where do the four ADPs come from in the second stage of glycolysis?

I think I understand your question, and stumbled upon it because i was wondering the same thing while studying for my Microbio test. I know its a year late, but someday someone else might need this ...
Ernesto Fernandez's user avatar
3 votes
Accepted

How are 6 "fixed" CO2 molecules joined toegther as glucose?

It's not really possible to break it down this way. The CO2 fixated by the RUBISCO enzyme generates two phosphoglycerate (2 x 3C) molecules from one ribulose bisphophate molecule (5C), while the rest ...
Roland's user avatar
  • 5,705
3 votes

Reason for conversion of glucose to fructose in glycolysis

If there is no glucose there is no need for glycolysis: I deduce from this truism that – at some early stage in the evolution of metabolism – a pathway resembling gluconeogenesis must have arisen ...
Alan Boyd's user avatar
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3 votes
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Human Body's rate of conversion of carbs, protein and fat into energy?

It is quite complicated, the speed of conversion of carbohydrates, protein and fat in to energy is definitely not linear and dependent on what the body is doing. You should be close to right in ...
Vilut's user avatar
  • 101
2 votes
Accepted

Starch vs Cellulose. What are the differences between Alpha and Beta glucose ring structure in them?

The reason the monomer units are shown as alternating orientation in the cellulose case and not for starch is due to the angles required for the bonds between the atoms involved. Note that in α-...
mgkrebbs's user avatar
  • 9,054
2 votes

What is the purpose of gluconeogenesis?

Before discussing gluconeogenesis it is necessary to be clear on the following: What organism you are considering Under what physiological circumstances gluconeogenesis is occurring What is the ...
David's user avatar
  • 25.7k
2 votes

How is the rate of gluconeogenesis controlled in the cell?

In mammals gluconeogenesis occurs primarily in the liver (together with the kidney to a much smaller extent). When the blood glucose concentration falls, it is the role of the liver to generate ...
David's user avatar
  • 25.7k
2 votes
Accepted

Why is the hexose monophosphate shunt called a direct oxidative pathway?

This answer is based on a 2002 autobiographical account of the work of Bernard L. Horecker entitled The Pentose Phosphate Pathway. Here he refers to “direct oxidative pathway” but does not ...
David's user avatar
  • 25.7k
2 votes

Why do cells not store glucose?

You most have misunderstood something... Cells do store glucose, however they do so by combining glucose molecules into longer storage molecules such as starch or glycogen. https://en.m.wikipedia.org/...
Jeppe Nielsen's user avatar
2 votes
Accepted

How is NAD+ used in lactic acid fermentation after it is oxidized from NADH?

Anaerobic Glycolysis As this question refers to glycolysis in the context of lactic acid fermentation it clearly relates to anaerobic glycolysis, which is why I added that to the question. I believe ...
David's user avatar
  • 25.7k
2 votes
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How is Glyceraldehyde 3-phosphate converted into glucose?

Advice to students of biochemistry This site is concerned with biology, not with biological entries in Wikipedia. Wikipedia is a voluntary effort to which anyone may contribute, and is full of errors ...
David's user avatar
  • 25.7k
2 votes

Finding out the best concentration for my plant extract to be used as drug for diabetes

You have to try to determine the best concentration. Usually there are multiple clinical trials, first in animals, then in humans to figure out the effective dose look for side effects compare the ...
Arsak's user avatar
  • 715
2 votes
Accepted

Why does hexokinase bond phosphate to the hydroxyl group on carbon-6 of glucose in glycolysis?

First of all some nitpicking, but the actual phosphorylation happens not to the Carbon-6 but to the hydroxyl group bound to this carbon atom. The mechanism is a nucleophilic attack of the hydroxyl ...
Chris's user avatar
  • 51.6k
2 votes

Proteoglycans vs Glycoproteins

More context would be helpful, but it's possible the data from the Quora post was incorrectly transcribed from a table on this biotech site, which states that the carbohydrate content of proteoglycans ...
acvill's user avatar
  • 8,296
2 votes

How does glucose uptake happen in the various tissues of the body?

As far as I am aware, all tissues have glucose transporters, but there are many different types with varying tissue distribution. A short review in Biophysical Reviews (2016) by Navale and Paranjapei ...
David's user avatar
  • 25.7k
2 votes
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What does the term 'glycogen mobilisation' mean?

I think the key to understanding mobilization in this context is in the second sentence: [Glycogen] can be broken down to yield glucose molecules when energy is needed. The authors are using ...
acvill's user avatar
  • 8,296
2 votes
Accepted

Glycemic Index and two-hour blood glucose response curve (AUC)? Where are the AUC charts?

You could search something like: https://scholar.google.com/scholar?hl=en&q=glycemic+index+AUC+glucose and your results will include papers that calculate glycemic index for some food based on ...
Bryan Krause's user avatar
  • 45.7k
2 votes

Why doesn't the cell just use one messenger?

A simple explanation for why there are intermediate messengers between stimuli (in this case adrenaline) and the final effector (the kinase). Multiple messengers in a signalling pathway create ...
fairy_bluebirb's user avatar
1 vote

Why do food items expire?

There are a number of reasons bacterial infection fungi infection Most fungi are not toxic in themselves but they release mycotoxins in the food, which are definitely toxic Maggot infection Other ...
Remi.b's user avatar
  • 68.1k

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